Pub operator JD Wetherspoon is seeking several million pounds in damages from its former sole property adviser, Van de Berg, for alleged breach of contract.
Van de Berg, based in Pinner, Middlesex, was retained by Wetherspoon's from 1990 to 2005 to act as an exclusive introducer of freehold properties.
Wetherspoon's is claiming Van de Berg and several formerly associated companies bought freeholds that should have been offered to Wetherspoon's but were let to rival companies, or were only offered to Wetherspoon's as leaseholds.
Wetherspoon's chairman Tim Martin, who is a qualified barrister, said: "A number of back-to-back property transactions took place over the last 15 years, when Van de Berg was our retained agent, of which Wetherspoon's was not aware, and there were some cases where properties were offered to Van de Berg as freeholds."
Van de Berg was unavailable for comment but Caterer understands that it is refuting the allegations. The case is expected to be heard in the High Court in December.